Goods removed from parcel

I would like to express my dissatisfaction at the service I've received from the SA Post Office. <br> I ordered a parcel online, which was shipped from Singapore to South Africa on the 27th August 2015, and arrived at the Johannesburg International Mail Centre (JIMC) on 16 September 2015. The parcel was held by Customs, and only sent to my local Post Office in Alexandra on 6th October 2015. My mother collected the parcel on my behalf on the 9th October 2015, and took it home. To my surprise, I found an empty box when I unwrapped the parcel on the evening of 9th October 2015. When I phoned the Alexandra Post Office, I was told there was nothing they could do & I had to fill out a form. I also contacted the seller, & was told the parcel had definitely been sent.<br> <br> I would like a thorough investigation by JIMC to figure out what happened to the headphones I ordered. I have paid both for the item as well as shipping costs, and now the goods have mysteriously disappeared!